Tissue and cell development have been studied extensively to determine the mechanisms by which maturation, maintenance and repair occur in living organisms. Generally, development of a cell or tissue can be considered as a transformation from one state or stage to another relatively permanent state or condition. Development encompasses a wide variety of patterns, all of which are characterized by progressive and systematic transformation of the cells or tissue.
In many instances it is desirable to control or alter the development of cells and tissue in vivo. It is hoped that means can be provided to restore or maintain the natural order of an organism after a debilitating injury, disease or other abnormality.
As will be appreciated by those skilled in the art, tissue and organic development involve complex processes of cellular growth, differentiation and interaction mediated by complex biochemical reactions. At the genetic level, development is regulated by genomic expression; at the cellular level, the role of membrane interaction with the complex biochemical milieux of higher organisms is instrumental in development processes. Moreover, remodeling of tissues or organs is often an essential step in the natural development of higher organisms.
A role for biologically active ions in cellular activity is well established. In Liboff et al., U.S. Pat. No. 4,818,697, techniques are disclosed for controlling the movement of a preselected ionic species across the membrane of a living cell. The inventors disclose that by exposing a region of living tissue of a subject such as a human or animal to an oscillating magnetic field of predetermined flux density and frequency, the rate of tissue growth can be controlled. For stimulating bone growth rate, a fluctuating magnetic field is tuned to the specific cyclotron resonance frequency of a preselected ion such as Ca.sup.++ or Mg.sup.++. Additionally, Liboff et al., in U.S. Pat. No. 4,932,951, disclose the use of cyclotron resonance tuning to control the growth rate of non-osseous, non-cartiliginous connective solid tissue. In U.S. Pat. No. 5,067,940, Liboff et al. disclose a method and apparatus based on cyclotron resonance tuning which allow the growth rate of cartilaginous tissue to be regulated. An even more important use of cyclotron resonance tuning which is of particular significance in the treatment of elderly patients is disclosed in Liboff et al. U.S. Pat. No. 5,100,373, which deals with a method and apparatus for treating and preventing osteoporosis, both locally and systemically. Additional patents granted to Liboff and his co-workers in the field of ion cyclotron resonance include U.S. Pat. Nos. 4,818,697; 4,932,951; 5,045,050; 5,059,298; 5,067,940; 5,077,943; 5,087,336; 5,088,976; 5,100,373; 5,106,361; 5,123,898; 5,143,588; 5,160,591, and 5,193,456. All of the above-cited patents are hereby incorporated by reference in their entirety. These patents address various applications of the concept of field induced changes in ion transport in biological systems. The primary requirement for these applications is for a time varying (AC, preferably sinusoidal) magnetic field and a static magnetic field oriented parallel to the AC field. Liboff postulates, without explicit theoretical support, that the maximum influence will occur when B.sub.ac =B.sub.dc. Furthermore, there is the requirement for specific frequencies of AC field to tune to resonance conditions for particular ions of interest.
The results of a number of studies suggest that low-intensity and low-frequency electric and magnetic fields may influence physiologic processes in biological systems. However, most theoretical models developed to date have been unable to establish a predictive association between low-intensity field exposure and biological results. Some models of electric and magnetic field interactions with biological systems, for example, have focused on endpoints associated with direct energy deposition into the system from the fields or from the induction of body currents, and suggest that a single variable, such as AC field intensity, is responsible for the observed results. Partially as a result of these incomplete models, many experimental reports fail to document all relevant field exposure parameters and do not establish a clear protocol for obtaining repeatable results. Inconsistencies between experimental results have subsequently been interpreted by some as evidence that electric or magnetic fields may not be the causal factors (e.g., Adair, 1991; 1992). While there is much theoretical support for resolving AC and DC fields into parallel and perpendicular components in order to determine how they will affect biological systems, experimental efforts often fail to document the relative orientation between the AC and DC fields. In other experiments, different field variables such as frequency, temporal duration of fields, and relative alignment with the local geomagnetic field have been characterized on an ad hoc basis without clear guidance from a theoretical model to indicate which parameters were critical (Adey, 1992; Blackman et al., 1985, 1988, 1990; Blackman, 1992; Liboff, 1985, 1992; Liboff et al., 1987; Smith et al., 1987; Thomas et al., 1986).
A variety of theoretical models have been developed to describe the interaction of different combinations of static (DC) and extremely-low-frequency time-varying (AC) magnetic fields with living systems. In fact, most theoretical works, including quantum mechanics texts (e.g. Yariv, 1982), focus exclusively on how an AC magnetic field oriented perpendicular to the DC magnetic field will alter the spin of an ion. Edmonds (1993), for example, recently developed a model that concentrated on the case of perpendicular AC and DC fields. Most of the above-described models are largely descriptive, without being predictive. The ion cyclotron resonance (ICR) model, originally formulated by Liboff (cf. Liboff, 1985, McLeod and Liboff, 1987) and discussed by Durney (1988), Halle (1988) and Sandweiss (1990), describes how unhydrated ions might have distinct resonance type responses caused by the local DC magnetic field.
The fundamental premise of the ICR model is that parallel magnetic fields tuned for calcium, or a limited set of other selected ions, enhance the passage of those ions across the plasma membrane of the cell, only when B.sub.ac =B.sub.dc.
Theoretical support for the plausibility of measurable biological effects occurring as a result of exposure to parallel DC and AC magnetic fields can be found in the work of Chiabrera and colleagues (Chiabrera and Bianco, 1991; Chiabrera et al., 1991; 1993; Bianco and Chiabrera, 1992). They applied their model to a variety of biologically active ions in addition to calcium using the charge to mass ratio for the unhydrated state, a condition that may exist in ion-ligand components of biological molecules. Chiabrera and colleagues suggested that ions affected by ICR model conditions might be located in binding sites formed by molecular crevices that would exclude hydration of the ions. Although the ICR model predicts enhanced responses by specific ions when the AC frequency corresponds with the ICR model conditions, which are different for each ion, it does not indicate how the response might vary with different AC flux densities. Thus, the ICR model does not anticipate the distinct response form subsequently predicted for increasing B.sub.ac at constant B.sub.dc and f.sub.ac.
Lednev (1991) incorporated Liboff's model, in a limited sense, in his examination of how parallel AC and DC magnetic fields might influence ions bound in ligand structures specific to Ca.sup.++.
The ion parametric resonance (IPR) model, originally disclosed in Ser. No. 08/329,980, differs from Lednev's model in three critical ways: it specifically includes a (-1).sup.n term multiplying the Bessel function prediction, the IPR model Bessel function argument is twice that of the Lednev model, and the IPR model considers a wider range of candidate ions, through an expanded understanding of the role of the ion in creating a biologically significant change.
The IPR model considers the potential effects on any unhydrated ion, or any entity that behaves like an unhydrated ion, presumably bound within a molecular structure, that can influence the observed biological response. The molecular structure may be composed of proteins, nucleic acids, or lipids, either singly or in any combination, as long as the structure itself requires an ionic cofactor to function. Extension to unhydrated ions beyond Ca.sup.++ can be inferred in part by the work of Liboff (1985, 1992) and Chiabrera and colleagues, op. cit.
Deficiencies in Background Art
Although for a long time it has been postulated that magnetic fields have potential effects on biological systems, there has been no clear evidence to date indicating the critical parameters influencing the effects. As a result, replication of observed effects has been limited at best. Lacking clear indication of the possible causes and forms of magnetic field influence, a linearly increasing effect with increasing AC field strength was assumed. However, Liboff gives no guidance beyond a maximum at B.sub.ac =B.sub.dc after which one must experiment unduly to obtain precise values of B.sub.ac and B.sub.dc that will be useful in treating a particular system. However, the present inventors have discovered that under the specific conditions identified herein, neither this assumption nor Liboff's postulated maximum effect when B.sub.ac =B.sub.dc is correct.
The work by Liboff et al. (1987) describing the transport of calcium/magnesium ions across a membrane of cells and bones considers specifically the physical motion of those ions as a result of the application of magnetic fields whose effect is to transform the random motion of those ions to a path matching the geometric form of the spiral channel postulated to provide passage across the membrane. The frequency for these ions is only the same at the fundamental. However, Liboff does not predict the hydrogen trigger at calcium tuning.
Although the "characteristic resonance frequency" of the IPR model is identical in mathematical form to that of the ICR model resonance, it will be seen that resonance as defined for the IPR model of this application is the mathematical inverse of that defined for the ICR model. Further, the mechanism of interaction postulated for the IPR model is distinct from that of the ICR model by virtue of abandoning a geometric concept and focussing on the ion's role within a molecular structure, such as an enzyme, protein, nucleic acid, and that the IPR model's consideration of candidate ions is, therefore, broader than is that of the ICR model. Since ##EQU1##
at constant B.sub.dc, a higher n requires a lower frequency.
Sandyk (1993) examined the application of magnetic fields to influence the pineal gland in patients with Parkinson's disease to moderate the melatonin caused hyperglycemia. However, the AC field flux densities applied were substantially below those postulated to be effective by the IPR model, assuming an approximate geomagnetic source of the ambient DC magnetic field. Further, three different orientations for the applied AC fields, with respect to a presumably fixed DC field, were required to produce an effect, obviating any requirement for parallel fields.
The work of Liburdy et al. (1993) also demonstrated the use of AC magnetic fields to control the influence of melatonin without a clear indication of the AC magnetic field orientation with respect to that of the ambient DC magnetic field. Lerchl et al. (1991) specifically considered the influence of parallel fields on pineal gland function, showing that a single selected combination of fields reduced the synthesis and production of melatonin. This single data point is between the maximal effect and null effect predictions by the IPR model, assuming Ca.sup.++ resonance. Lerchl further considers the distinction between parallel and perpendicular fields, postulating them to follow a cosine law form, although this was not substantiated by any data. Although these works, taken together, appear to suggest a likely effect on either melatonin production, or its action in vivo, or both, they each give results for single combinations of applied magnetic fields without any further guidance for how these effects might change with variations in AC flux density, frequency, or DC flux density. As will be shown below, no person of ordinary skill in the art at the time of these publications would have been motivated to demonstrate the parallel AC and DC magnetic fields would be able to control precisely the function of melatonin, either applied or as produced by the pineal gland, in the controlled and distinctly predicted non-linear form predicted by the IPR model. Further, no person of ordinary skill in the art at the time of these publications would have been motivated to demonstrate the three distinct responses shown under parallel (on or off resonance) and perpendicular AC and DC magnetic fields, indicated by the present application, across a critical range of AC flux densities.
Absent from any of the aforementioned arts is any recognition of:
(a) the variation in critical influence of the strength (flux density) of the AC magnetic field on the magnitude of magnetic field influence on a biological system;
(b) the importance of reducing the static magnetic field perpendicular to the AC magnetic field to near zero value in order to distinctly get the IPR model predicted result;
(c) the role of AC frequency;
(d) the potential for a single exposure condition to differentially stimulate multiple ions concurrently;
(e) evidence of the unique role of a variety of otherwise biologically significant ions, including but not limited to hydrogen, sometimes critical, in a biological system's response to a magnetic field;
(f) the explicit recognition of peak AC field measurements (in contrast to rms) as the appropriate metric.
(g) a clearly prescriptive identification of how the system might differentially respond to variations in B.sub.ac (with B.sub.dc and f.sub.ac constant) except for a postulated effect when B.sub.ac =B.sub.dc (with B.sub.ac interpreted by some experimenters as rms and by others as peak).
(h) indication of the distinction in biological/chemical system response between exposure to parallel and exposure to perpendicular AC and DC magnetic fields, and the critical importance of maintaining strictly parallel fields in order to get the distinct response form predicted by IPR model;
(i) the role of the DC field in selecting an ion or in increasing the off-resonance effect wherein the same AC field could either change f.sub.ac or B.sub.dc to make no effect.
It has also been found that the ion cyclotron resonance condition disclosed by Liboff is a special case of the ion parametric resonance model that is not extendable via harmonics, as Liboff and others have assumed to date.
In the IPR model of application Ser. No. 08/329,980, magnetic field interactions with ions are characterized by a frequency index, n, defined as the ratio of the (ion specific) cyclotron resonance frequency to the applied AC frequency. When n for a given ion has integer value, the system is said to be in resonance for that ion. When n=1, resonance is also found with Liboff's ICR model.
Theoretical models developed to date have been unable to establish a detailed predictive association between low-intensity field exposure and biological results. Some models of electric and magnetic field interactions with biological systems focus on endpoints associated with direct energy deposition into the system from the fields of induction of body currents and suggest that a single variable, such as AC field intensities, is responsible for the observed results. Partially as a result of these implicit models, many experimental responses fail to document all relevant field exposure parameters and do not establish a clear protocol for repeatable results. Inconsistencies between experimental results have subsequently been interpreted by some as evidence that electric or magnetic fields may not be the causal factors (cf. Adair, 1991, 1992).
Most experimental efforts heretofore have failed to document or consider the importance of the relative orientation between the AC and DC fields. In some experiments, different field variables such as frequency, temporal duration of fields, and relative alignment with the local geomagnetic field have been characterized on an ad hoc basis without clear guidance from a theoretical model to indicate which parameters were critical (Adey, 1975, 1988 a, b, 1992; Blackman et al., 1985, 1988, 1990; Blackman, 1992; Liboff, 1985, 1992; Liboff et al., 1987 b; Smith et al., 1987; Thomas et al., 1986).